Lieutenant Phelps reported the results of a 5 October reconnaissance: "I examined the fort [Henry] carefully at a distance of from 2 to 2 1/2 miles.... The fortification is quite an extensive work and armed with heavy guns, mounted en barbette, and garrisoned by a considerable force.
"It is situated about 1 1/2 miles above the head of Panther Creek Island.... There is no channel upon one side of the island, and a narrow and somewhat crooked one upon the other, which continues so till within a mile of the fort, where the water becomes of a good depth from bank to bank, some 600 yards."
Detailed knowledge and careful preparations in large measure provided for the ultimate success of the February offensive operations against both Forts Henry and Donelson with the objective of driving the Confederates out of Kentucky where they held a line across the southern part of the state.